01
Why Endpoints Are the Primary Attack Surface
Endpoints — the laptops, desktops, mobile devices and servers that users interact with — are where the vast majority of attacks begin. Phishing emails land in mailboxes. Malicious downloads execute on workstations. Ransomware spreads device to device across the network.
Traditional antivirus detected known malware by signature. Modern attacks use fileless techniques, living-off-the-land binaries, and zero-day exploits that signatures can't detect. Modern endpoint protection uses behavioural analysis — detecting what the malware does, not what it looks like.
Modern endpoint security is not about detecting viruses. It's about detecting malicious behaviour — and stopping it before damage occurs.
02
Microsoft Defender for Endpoint
Microsoft Defender for Endpoint (MDE) is the enterprise EDR platform included with Microsoft 365 Business Premium and most E3/E5 plans. For businesses already using Microsoft 365, it's the most cost-effective endpoint protection platform available.
Key capabilities
Endpoint Detection & Response (EDR)
Behavioural detection that identifies attack patterns — not just known malware signatures. Alerts on suspicious process trees, unusual network connections, and attacker tools.
Automated Investigation & Remediation
When an alert fires, Defender automatically investigates the root cause and can automatically remediate — quarantine files, isolate devices, reverse changes.
Attack Surface Reduction (ASR)
Rules that block specific attacker techniques — blocking Office applications from spawning child processes, blocking executable content from email, preventing credential theft from LSASS.
Threat & Vulnerability Management
Continuous assessment of endpoint vulnerability posture — which devices have which vulnerabilities, with prioritised remediation guidance.
03
Deployment Configuration
Onboarding devices
✓Onboard all Windows devices via Intune (Group Policy or Configuration Manager for larger environments)
✓macOS onboarding via Intune MDM enrollment
✓Mobile devices (iOS/Android) via Intune MAM (app-level protection) or MDM enrollment
Security baseline
✓Enable cloud-delivered protection — real-time cloud lookups for unknown files
✓Enable automatic sample submission — suspected malware sent for analysis
✓Enable tamper protection — prevents attackers from disabling Defender
✓Enable PUA protection — block potentially unwanted applications
✓Set EDR in block mode — Defender takes remediation action even if another AV is primary
Attack Surface Reduction rules — recommended for SMB
✓Block Office applications from creating executable content
✓Block execution of potentially obfuscated scripts
✓Block Win32 API calls from Office macros
✓Block credential stealing from LSASS
✓Use advanced protection against ransomware
04
Monitoring and Alert Response
Defender for Endpoint generates alerts across multiple severity levels. The response approach varies by severity — but all alerts should be investigated.
| Severity | Examples | Response |
|---|
| Informational | Unusual login time, new device | Review weekly in Security portal |
| Low | Suspicious script execution, blocked malware | Investigate within 24 hours |
| Medium | Credential access attempt, lateral movement | Investigate within 4 hours |
| High | Active ransomware, data exfiltration | Immediate — escalate to De4sec now |
Microsoft 365 Defender portal
All endpoint alerts, incidents, and investigations are centralised in the Microsoft 365 Defender portal (security.microsoft.com). De4sec provides managed monitoring of this portal — reviewing alerts, investigating incidents, and responding on behalf of clients.
05
Endpoint Security for Mobile Devices
Mobile devices — particularly personally-owned phones used for work email and Teams — represent a significant gap in most endpoint security strategies. The device isn't enrolled in Intune, doesn't have EDR, and may access corporate data with no security controls.
Mobile Application Management (MAM)
✓Intune MAM without full device enrollment — apply data protection policies to specific apps only
✓Require PIN to open Outlook, Teams, SharePoint apps
✓Prevent copy/paste from corporate apps to personal apps
✓Remote wipe of corporate data from personal device if device is lost or employee leaves
Conditional Access for mobile
✓Block unmanaged mobile devices from accessing sensitive data
✓Require Intune App Protection Policy (APP) compliance for mobile access
✓Allow browser-only access from unmanaged devices — no downloads
06
De4sec Endpoint Security Service
De4sec provides Microsoft Defender for Endpoint deployment and managed monitoring as part of our managed IT and cybersecurity service.
Deployment
Onboard all devices, configure security baseline, deploy ASR rules, integrate with Intune compliance policies.
Managed Monitoring
24/5 alert monitoring via Microsoft Defender portal. Critical alerts escalated immediately. Weekly review of informational and low-severity alerts.
Incident Response
When a high-severity alert fires, De4sec investigates, contains, and remediates. Post-incident report provided with root cause analysis.
Reporting
Monthly endpoint security report: device compliance, patch status, alerts by severity, open vulnerabilities.
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